Why do I receive an error when building a RTWT for simulink that contains an Embedded MATLAB block in Simulink 7.6 (R2010b)?

I receive this error when I build a RTW target， I use the embedded matlab function and I wrote the code by M-code.

Unexpected or internal error encountered in "in CGIR: .\utils\rtwcg_prop.cpp line 3109: RTWCG::propMatrixMul - invalid operator dimensions '[5, 3] * [7]'". Please report this to The MathWorks if you can cause it to recur.

and the diagnose window give the information： Error reported by S-function 'sf_sfun' in 'embednpc131217/NPC controller/ SFunction ': Errors occurred during codegen.

thanks